Creating a macOS bootable USB drive (or "bootstick")

If you are having trouble using the "command-option-r" method of booting to show the macOS as an installable operating system for your mac, you can make an installer bootable USB drive to do the installation:

You will need:

16 GB or larger flash drive that can be completely reformatted.

A functional Apple system

The current macOS full installer from the AppStore (if you do not have an account to download things from the AppStore, please contact the Mac Engineering team).

If you need to get an older version of macOS, you can find AppStore links at this page: https://support.apple.com/en-us/HT211683

Process:

Download or otherwise transfer the macOS installer to your /Applications folder.
Launch Disk Utility found in Applications → Utilites
Plug the USB flash drive into the functional system
In Disk Utility, select your USB flash drive.(You will want to select the device, and not the partition) Click the Erase button.
In the window that appears, select the following options:

Name: 'Untitled'
Format: Mac OS Extened (Journaled)
Scheme: GUID Partition Map

Click Erase
Once the drive has been erased, quit Disk Utility, open the "Terminal" application and run the following command:

Important Note

The final installer for macOS 12, 13 and 14 are over 13G, so you will need a 16G boot stick for them! The final installer for macOS 15 and up are over 15G, so you will need a larger boot stick (32G or greater) for those

For Monterey (macOS 12), the command would be:

macOS 12

sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia \
  --volume /Volumes/untitled \
  --nointeraction \
  --downloadassets

For Ventura (macOS 13), the command would be:

macOS 13

sudo /Applications/Install\ macOS\ Ventura.app/Contents/Resources/createinstallmedia \
  --volume /Volumes/untitled \
  --nointeraction \
  --downloadassets

For Sonoma (macOS 14), the command would be:

macOS 14

sudo /Applications/Install\ macOS\ Sonoma.app/Contents/Resources/createinstallmedia \
  --volume /Volumes/untitled \
  --nointeraction \
  --downloadassets

For Sequoia (macOS 15), the command would be:

macOS 14

sudo /Applications/Install\ macOS\ Sequoia.app/Contents/Resources/createinstallmedia \
  --volume /Volumes/untitled \
  --nointeraction \
  --downloadassets

Important Note

The final installer for macOS 15 and up are over 15G, so you will need a larger boot stick (32G or greater) for those

When the command has finished running and you return to the command prompt, your "Untitled" USB drive will be named "Install macOS Big Sur" (or "Catalina" or "Monterey", etc...) and then you can use that to boot your mac by inserting the USB drive and starting the computer holding down the "option" ⌘ key to erase the computers internal hard disk and then install macOS for non-Apple-Silicon macs.

For Apple Silicon ("M1", etc) Macs, you would boot them holding down the power key until you see the "Startup Options" to be able to select your USB drive for startup. You can then follow this link as to how to wipe-and-reload a system after that!